The effective current in a field-effect transistor (FET) is an important parameter to measure for accurate performance benchmarking in partially depleted silicon-on-insulator (SOI) technology. When measuring this parameter of a FET, the FET must be switched from an off-state to an on-state. However, when switching the FET, the time for the body of the FET to reach a steady-state condition is more than the time it takes to switch on the FET, and hence during high-speed operation, the body charge remains nearly fixed at its starting value. When measuring devices, however, the time needed for accurate readings of standard instrumentation is large, compared to the characteristic time for the body to charge to steady state. Very specialized high-speed test equipment with specialized probe stations have been developed that include a fast sampling speed, but these devices are not consistently accurate and are extremely expensive for use in manufacturing.